Abstract:

Risk zoning of flood disaster is the base of flood risk management.The advance in resolution of data can guide flood control，and flood insurance in a macroscopic view is available.Taking the catchment area along Xiangjiang River in Hunan Province as an example,and on the basis of elementary principles of natural disasters risk assessment,calculative model was established to obtain comprehensive flood disaster risk value which was computed by the integrated dangerous degree and comprehensive socioeconomic vulnerability.Based on 30 m ASTER Global Digital Elevation Model (GDEM) data,climate data from 37 meteorological stations during 1971 to 2006,and 2008 socioeconomic statistic data,with the support of ArcGIS and quantitative geoscience methods,the regionalization map of comprehensive risk of flood disaster in study area was drawn by calculating proportion of risk areas.The regionalization map divided general risk assessed results mainly into four grades,that is,the lower risk region,moderate risk region,higher risk region and the highest risk regions.The results show that the highest integrated dangerous degree of flood disaster areas are mainly distributed in Xiangyin and ChangZhuTan region which along the lower reaches of Xiangjiang River.The highest comprehensive socioeconomic vulnerability areas is distributed in urban that in high population density.Xiangyin,ChangshaZhuzhouXiangtan and Hengyang belong to the highest comprehensive flood disaster risk areas.The results can provide quantitatively theoretic basis for environmental management and ecological risk decisionmaking